This invention relates to motor driven pumps and more particularly to a vertically driven pump in which the drive shaft between the motor and the pump is of considerable length.
It is well known that vertically driven pumps are used to pump water from wells, lakes and rivers, for lift stations in sewage lines, and waste treatment facilities to name a few. These pumps are used in wet, dirty hostile environments and continually need maintenance attention in that most vertical pumps contain a shaft of sufficient length from the pump to the motor which allows a vibration great enough to destroy the packing which then permits leakage of the pressure built up inside the pump. It has been found that when the distance from the pump to the motor is greater than 12 inches for a solid motor shaft with a 1-3/8 inch diameter shaft or any hollow motor shaft, that vibration occurs due to wear and loading of the impeller, accumulation of foreign matter collecting on the shaft and the fact that metal has a degree of flexibility allowing a faint bow of the shaft under loaded conditions and a high rate of turn.
It has been determined that a vertically driven well pump with a hollow motor shaft 24 inches long and 1-3/8 inches in diameter destroyed the packing of the pump on an average of once every week. The pump was then provided with a more modern mechanical seal with two hard smooth surfaces pressed against one another, one of which was stationary to the pump housing, the other rotating with the shaft. The vibration chipped the mechanical seal until it was of no value. The mechanical seal was removed and the packing was replaced, with a new packing, then the device of the invention was installed on the drive shaft and the pump was operated for a period of 30 days. An inspection of the pump and packing showed a normal wear as would have occured in a horizontal pump. With the device of this invention in place a mechanical seal was then installed on the pump for better efficiency of the pump operation. An inspection was performed after an additional 60 days of operation and there was no damage to the seal, pump or stabilizing bearing.
It is therefore an object of the invention to provide a stabilizer for a pump shaft which will permit long periods of operation of a vertically driven pump with very little wear of the packing.
Another object is to provide a simple inexpensive device which will stabilize a drive shaft for a vertically driven pump to prevent damage to the seals of the pump.
Yet another object is to provide a stabilizer for a motor driven pump which uses a long shaft for vertical or horizontally driving the pump.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of preferred embodiments taken in conjunction with the drawings.